Graham- I'm not familiar with the ADI powders, so I'm not sure how hot you're loading, however your game plan sounds about right. I shoot an H&H also and I have some Federal brass that is on the 10th loading and no problems so far. Of course the last four have been cast loads as I am trying to find something that won't aggravate the bulged disk in my neck. Mine is a Win Mod 70, Classic stainless, (nearly a necessity up here). Anyway if you decide to go cast try an NEI .375-304-GC, I bought a couple hundred from Bullshop on the other forum and my rifle loves them. Right now I'm trying to find the recoil level that my neck can stand vs. accuracy vs. enough energy for a brown bear. Once I get it all wrung out and dialed in I'll be sure to post the results. Take care
-Klaus